After the underground utilities are electronically designated using either electromagnetic pipe locators, acoustic pipe locators, ground penetrating radar or a combination of any of then, the next stage in data reliability, equivalent to Quality Level A, is obtained by Vacuum excavation AKA potholing.
GEOVAC a Division of Bess Testlab, Inc. uses Non-Destructive Air-vacuum Excavation (potholing) to expose the utilities being survey to determine their exact depth and location. Precisely locating underground utilities help the designers to plan their construction project to eliminate potential damage and un-necessary relocations.
Our powerful Vacmaster's systems 4000 and our skilled technicians are capable to dig potholes faster than any other system that we know using air.
This mode of excavation uses a combination of high-pressure air and a powerful vacuum to safely remove the soil that encloses the utility eliminating the risk of damaging the utility usually associated with traditional methods of mechanical excavation.
After the pothole is completed and the utility data is collected then the back filling of is done using the native extracted material which is compacted to 95% level using a pneumatic rammer.
Back filling the holes using other materials such as CDF slurry and class II bed rock is available if requested.
Temporary and permanent surface restoration is done by our crew as needed.
The steps for the potholing operation are as follows:
- Utility designating by Underground Service Alert or private locate, as needed.
- Traffic control setup.
- Surface removal: either by jack hammering a 12" x 12" square opening or by drilling a 11" diameter core using a patent-pending setup.
- Air-vacuum excavate pothole to expose utility
- Data Collection / survey
- Back filling pothole using native or foreign materials, as needed
- Surface restoration: Temporary or permanent as needed.
- Placement Utility survey mark: PK nail, stake, paint, etc.
- Traffic control removal.
Who we have worked for? Following is a partial list of some of our clients that we have performed vacuum excavation & potholing services:
- Caltrans District 4 - SF Bay Area
- Caltrans District 5 - San Luis Obispo / Santa Barbara/ San Benito
- Caltrans District 6 - Central Valley
- SBMUD
- Valley Transportation Authority - VTA
- City of Pleasanton
- FCI Constructors
Other uses of Vacuum Excavation Equipment
The vacuum excavation technique is used not only to expose utilities but also for other uses that are benefited by the non-invasive and environmentally friendly technology. Following are some of the additional applications:
- Slot trenching
- Sign & pole installation
- Digging for the installation of Devices for Cathodic Protection
- Mud removal
- Remote digging (400 ft reach)
- Water removal from catch basins, manholes, meter boxes and utility vaults
- Excavation around tree roots
- Rail road tie clean outs.
- Pond excavation
- Elevator shaft cleanouts
